LoneRangeFinder Loc: Left field

Curious if anyone has tried combining a macro lens with a teleconverter to add working distance

Macronaut Loc: Redondo Beach,Ca.

I think Kurt (Orionmystery) said he uses them. Maybe check with him. No doubt his photography is superb.

rmpsrpms Loc: Santa Clara, CA

I use Vivitar 2x Macro Focusing Teleconverters for this purpose. The Vivitar is not only optimized to work at higher magnifications, but includes a focusing helicoid that gives extra / adjustable extension in the same component. It was designed to "convert" a standard 50mm kit lens into a 100mm Macro lens, and it does a decent job of it. Or it will turn a 100mm macro into a 200mm supermacro capable of >>1:1 magnification.

The general problem with teleconverters is they reduce the aperture the same amount they increase magnification. Depending on your lens settings, this can result in "empty magnification" or even cause a serious reduction in image quality.

Interestingly, depending on how you crop and downsize, adding a teleconverter can actually improve image quality. You just need to be careful with your settings and workflow.

DigitalDon Loc: Calgary, Alberta

I use a Nikon AF-S MICRO NIKKOR 105mm with a Nikon 2x converter 95% of the time. There is no degredation and it does bring in approx. 2x. The ONLY time I remove the converter is if I can't back up enough to frame the subject properly. I do not use a flash but I also admit most of my macro shots are in good sunlight.

Nikonian72 Loc: Chico CA

"Empty magnification" has to do with reducing sensor size (therefore reducing pixel count), or over-enlarging an image during post. It has nothing to do with lenses.

Per http://www.idigitalphoto.com/dictionary/empty_magnification : "Increase in size of image which does not increase information. * Magnfication which does not contribute to improved resolution or resolving power and which is beyond what the system can deliver. * E.g. enlarging a photograph beyond a certain point only creates a bigger picture, with no increase in usable information."

Apaflo Loc: Anchorage, Alaska

Using teleconverters for macro work isn't as well known as it should be, but the effects and at least some discussion of it has been around for a fairly long time. John Shaw, in his now classic book "Closeups in Nature", devoted space to a lot of detail about using TC's with or without extension tubes. Details like what the difference is if the extension tube is between the camera and the TC or between the TC and the lens.

The long and short of it is that TC's work very well when focusing at macro distances. Virtually all of the normal problems associate with TC's are minimized because of the short focus distance. Only the well corrected center of the optical path is used, and hence all of the magnified aberrations that affect TC use at normal distances are absent. Any decent 7-element 2X TC will work well. The better AF TC's are supurb for AF lenses. (1.4X TC's are fine, but not used as much just because 2X TC's are more effective.)

As an example, like others I've been using Vivitar 2X Macro Focusing Teleconverters for years. My "standard field kit" is a 105mm f/2.8 Lester A Dine macro, a Vivitar 2X Macro Focusing TC, and an Olympus TCON-35 +2.85 Diopter lens.

The cost of the Vivitar 2X Macro Focusing TC runs less that $50 on eBay. There are also sometimes examples of the Kino Optical made 2X focusing TC (I forget if it is labeled Kiron or Panagor), and that is equally good and low cost too. The one catch to both of those is that they came from a time before AF lenses, and will not work at all with a Nikon G lens. Strictly manual.

Even though I use Nikon cameras, these days it is easy (for manual focus macro work) to use adapters to different brands of lens mounts. Because the Vivitar 2X Macro Focusing TC is available at such low prices, I have them in at least three different mounts.

rmpsrpms Loc: Santa Clara, CA

Reducing sensor size/pixel count does not result in empty magnification if pixel pitch is kept the same. This is simply called "cropping". I think what you meant was "reducing sensor size with the SAME pixel count, correct?

Increasing the image size on a given sensor has the same effect. Once you're well beyond the diffraction limited aperture for your sensor, any increase in image size on the sensor is empty magnification. So if you are shooting at small aperture, and add a teleconverter, you just spread that low-resolution image across more pixels.

The only time using a teleconverter is not "empty" is when the effective aperture is kept large enough to still provide pixel-level resolution.

For landscape and even portrait photography, where effective apertures are nearly the same as nominal, teleconverters are simple to understand and implement. But because diffraction can be much more of a problem when shooting macro, you need to take more care to keep from degrading image quality when using them.

LoneRangeFinder Loc: Left field

I may have some time to do a few tests over the weekend. I was more interested in increasing my MWD for nailing some subjects that were not as approachable. The interesting thing is this: The EXIF when coupling the 1.4x TC with the 105 reads as "150mm"; in fact it's functionally 147mm. Perhaps it just rounds up?

naturepics43 Loc: Hocking Co. Ohio - USA

What brand lens & TC are you using? I had an older Nikon 105D & used an old Sigma 1.4TC & as I recall, they showed 147mm in EXIF. I was disappointed with the older Sigma TC BUT I wasn't using it properly.

I've used a Tamron SP 1.4TC on my Tamron SP 180 macro with good results & great MWD! (This combo does NOT report the use of the TC in EXIF)

Apaflo Loc: Anchorage, Alaska

Actually the "1.4x" is a "1.4142x" TC, so if the lens is actually 105mm, it becomes when focused at infinity a 148.5mm focal length. Of course, it probably isn't a 105.000mm lens anyway... but if you are focusing it down to a 1:1 magnification it is far less than 105mm in actual use. Probably more like 80mm or a bit less. And since f/stop is the ratio of the aperture size and focal length, and the apertures size stays the same when close focused, the f/stop is greater. Basically, figure that if the lens is marked (which the new G lenses are not) the actual f/stop at 1:1 is very close to 1.4x the marked f/stop. Nikon's camera's will indicate an adjustment for that with a G lens, but I don't know how accurate it is.

It doesn't make a lot of difference, given through the lens metering. But what does make a difference is realizing that an actual f/stop of f/22 is about where diffraction becomes significant with a full frame sensor. With good sharpening technique you can correct for a bit more than that, and maybe f/27 is about the limit. At an effective aperture of f/32 or more you are going to lose resolving power. (Reduce those figures by 1 f/stop for APS-C 1.5x cropped sensors.)

IShootEverything Loc: TN

My Canon 100mm macro does not work with the 2x extender

LoneRangeFinder Loc: Left field

The Nikkor 105G and the Nikon TC-14E II TeleConverter‎ (1.4x)

rmpsrpms Loc: Santa Clara, CA

Exactly. if you are operating at f/16 nominal, then at 1:1 you are at f/32 and you will be effectively diffraction limited. Adding a 1.4x TC will take you to f/45, and while it gives you a bigger image there is not much more information in that image. The extra 1.4x magnification is "empty". In order to get more information, you need to increase the aperture by 1 stop to f/11 nominal. The effective aperture will then be f/32 and you will be able to pick up more detail in the image vs without TC. For a 2x TC, you would need to increase aperture to f/8 to keep the same f/32 effective.

This is only the case if the APS-C sensor has the same number of pixels as the FF sensor. For example, the D610 and D7100 both have 24MP sensors, but the D7100 pixel pitch is 30% smaller so needs to have a larger aperture to maintain the same relative diffraction pattern.

Screamin Scott Loc: Marshfield Wi, Baltimore Md, now Dallas Ga

I've got a couple of the Vivitar 2X macro focusing converters, but seldom use them with any of my lenses

tinusbum Loc: east texas

i have a sigma 1.4 tele converter i used with my 105 a couple years ago.i think it degraded the pic somewhat but its been longer that my memory banks hold information